Stats Flashcards
Formulas provided vs recall
Circumference of a circle
2piR
% error (uncertainty) formula
( 2 x absolute uncertainty / quantity measured ) X 100
Magnification formula
size of image / size of real object
Rf formula
Surface area to volume ratio formula
Genetic biodiversity formula
Cardiac output formula
cardiac output = heart rate × stroke volume
Respiratory quotient
Microorganism population growth formula
Efficiency of biomass transfer formula
Temperature coefficient (Q10)
Chi squared - provided
Spearman’s rank correlation coefficient - provided
Standard deviation - provided
Students t Test - unpaired - provided
Students T Test - paired - provided
Simpsons Index - provided
Why is standard deviation a better measure of spread than range
Less effected by extreme values
What is the null hypothesis
There is no significance difference between….the things you are measuring
What does the chi-squared test look at
Differences in frequencies between groups
Degrees of freedom for chi squared
Number of classes - 1
How to tell if your chi squared values are significant
If my value is greater than or equal to the critical value = it is significant = reject null hypothesis
If my value is less than the critical value = not significant = can’t reject null hypothesis
When to use a chi squared test
- data is about frequency’s for different categories
- each person / thing only appears once in the results
Categorical + independent
How to work out expected frequency in chi squared if there is more then one row / column
Can’t just distribute evenly
(Row total X column total) / overall total
